The Six Chair Challenge started on the 27th July, where it was shown that Sharon Osbourne was mentoring the Girls category. It was also revealed that Simon Cowell would be mentoring the Groups, Nicole Scherzinger would be mentoring the Overs and Louis Walsh would be mentoring the Boys.
In a change to previous years, each judge faced their category alone while the other judges sat on the sidelines offering their critique.
| Judge | Category | Chairs | |||||
|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | ||
| Cowell | Groups | Jack & Joel | Rak-Su | The CutKelvins | Sean & Conor | Lemonade | New Girlband |
| Scherzinger | Overs | Matt Linnen | Tracey Leanne Jefford | Talia Dean | Slavko | Kevin Davy White | Berget Lewis |
| Osbourne | Girls | Deanna Mussington | Grace Davies | Holly Tandy | Rai-Elle Williams | Georgina Panton | Alisah Bonaobra |
| Walsh | Boys | Lloyd Macey | Spencer Sutherland | Leon Mallett | Aidan Martin | Anthony Russell* | Jack Mason |
- Although put through to Judges' Houses, it was confirmed that Anthony Russell had withdrawn due to "personal reasons". His replacement was announced as Sam Black, who was originally eliminated during Bootcamp